This invention relates to a fastener which is used for fastening such a compressible sheet as an insulator sheet or a carpet to a supporting panel.
To fasten an insulator sheet or a carpet to the dashboard in an automobile, for example, Japanese Utility Model Application Disclosure No. Sho 56(1981)-64839 discloses a metal plate molded as bent roughly in the shape of the letter U which provides the desired fastening by having the central piece thereof spot welded to the dashboard (supporting panel), causing the two raised pieces at the opposite ends thereof to be inserted through the matching holes bored in advance in the insulator sheet or carpet and bent down onto the supporting panel, or which provides the desired fastening by having one of the raised pieces thereof folded back in the shape of a claw, having the claw tightly nip a folded edge of the supporting panel and causing the other raised piece thereof to be inserted through a matching hole bored in advance in the insulator sheet or carpet and bent down onto the panel. With either of the versions of the fastener taught by the invention of the utility model application, the operator is required to bend the raised pieces with his fingers and, therefore, is often exposed to the possibility of sustaining injuries to his fingers. Further, since the fastening is obtained simply by bending the raised pieces down onto the panel with the fingers, when the insulator sheet or carpet is exposed to any external force tending to separate it from the supporting panel, there ensues the possibility that the raised pieces now in a bent form will be bent back in the direction of resuming the original shape and inducing unwanted release of the insulator sheet or carpet. The version of the fastener which involves causing the central piece thereof to be fastened to the panel by spot welding inevitably calls for the work of welding, which consumes much time and labor and entails the risk of rusting of the welded portion of the panel. The version of the fastener which involves causing the claw to be fastened as hooked on the edge of the panel inevitably entails the disadvantage that a complicated operation is required to bend the metal plate to the desired shape.